Chapter 45: Celiac Plexus Block Using CT Guidance

INDICATIONS

The major indications for celiac plexus block (CPB) include abdominal pain which is nonresponsive to less aggressive analgesic interventions and which emanates from:

• The pancreas^1,2

• The liver

• Gallbladder

• Omentum

• Mesentery

• The alimentary tract from the stomach to the transverse large colon,³ which is of a visceral and not a somatic nature

These indications include pathology that is both of a benign as well as a malignant etiology.

Neurolytic CPB is typically reserved for cancer-related pain, while it is more common that local anesthetic and occasionally steroid injections are reserved for benign type of pain. Following performance of CPB using 50% to 100% alcohol for malignant pain, an early meta-analysis found that pain relief was “good or excellent” in 89% of 989 patients for the first 2 weeks following the block.⁴

PREOPERATIVE CONSIDERATIONS

• Determine the etiology of painful processes of the abdomen. It is essential to rule out nonvisceral causes.

• Perform somatic blocks prior to undertaking CPB.

• Intercostal nerve blocks (ICNB) may be one such approach to using somatic blocks in an effort to differentiate somatic from visceral etiologies.

• Judicious use of local anesthetic agents for ICNB may help determine whether or not a pathologic process has primarily a somatic origin versus a sympathetic one.

RELEVANT ANATOMY

• Several of the abdominal viscera receive innervation through the celiac plexus.

• Sympathetic innervation is derived from the anterolateral horn of the spinal cord as axons from T5 to T12 leave the spinal cord with ventral nerve roots to join white rami communicantes (WRC) in route to the sympathetic chain.

• These axons do not synapse in sympathetic chain; instead, they pass through the chain to synapse at distal sites.

• The celiac plexus includes several ganglia, these being the celiac, aortic, renal, and superior mesenteric ganglia.

• Postganglionic nerves accompany blood vessels to visceral structures.

• Preganglionic fibers from T5 to T9 travel caudally from the sympathetic chain along the lateral and anterolateral aspects of the respective vertebral bodies.

• The greater splanchnic nerve arises from the T9 and T10 levels.

• The celiac plexus (Figure 45-1) sits anterior to the aorta, epigastrium, and crus of the diaphragm. Fibers comprising the celiac plexus arise from preganglionic splanchnic nerves, parasympathetic preganglionic nerves from the vagus nerve (CN X), some sensory nerves from the phrenic and vagus nerves, and postganglionic sympathetic fibers.

• Complete sympathetic denervation of the gastrointestinal tract, such as may occur following CPB renders an individual likely to develop increased peristalsis due to unopposed parasympathetic nervous system activity.

The celiac plexus is in actuality the confluence of three distinct pairs of ganglia; the celiac, superior mesenteric, and aorticorenal ganglia, respectively. Afferent nociceptive ...